If you have a frame that's doesn't have a wire on the back for hanging, you don't need to go searching for a way to hang it up. All you need is a screw and an old pop can.
In order to pull this off, we'll need to remove the pull tab from the pop can without damaging it. With a small pair of pliers, grab the short end of the tab and pull it out slowly — the rivet ring should still be intact once you get it off. Then, just thread a screw through the rivet ring and onto the back of your frame. The top of the tab will provide a nice small hole from which you can hang the frame on a nail in your wall. Hit the link for a full photo walkthrough.